Induction welding with an electromagnetic field concentrator

An induction welder for induction welding thermoplastic material, comprising:

• a coil configured to generate an electromagnetic field;
• and
• a concentrator configured to concentrate the electromagnetic field onto a region of the thermoplastic material, the concentrator comprising a face surface and a receptacle, the receptacle projecting vertically into the concentrator from an opening in the face surface to an end of the receptacle, the receptacle extending laterally within the concentrator between opposing sides of the receptacle, and the receptacle extending longitudinally within the concentrator along a centerline;
• the coil vertically recessed into and extending longitudinally along the centerline through the coil receptacle.

An induction welder for induction welding thermoplastic material, comprising:

• a coil configured to generate an electromagnetic field;
• and
• a concentrator configured to concentrate the electromagnetic field onto a region of the thermoplastic material, the concentrator comprising a face surface and a receptacle, the receptacle projecting vertically into the concentrator from the face surface to an end of the receptacle, the receptacle extending laterally within the concentrator between opposing sides of the receptacle, the opposing sides of the receptacle flaring laterally out as the receptacle extends vertically to an opening in the face surface, and the receptacle extending longitudinally within the concentrator along a centerline;
• the coil disposed in and extending longitudinally along the centerline through the coil receptacle.